Getting started

Install via npm or yarn:

npm install validator-fns
# or
yarn add validator-fns

Import everything:

import * as V from 'validator-fns';

Or just what you need (all examples in these docs will use this style):

import { string, required, email } from 'validator-fns';

Combine functions to create your validator:

const validateRequiredEmail = string(
  required('Email address is required.'),
  email('Must be a valid email address.')
);

Later, execute validator:

// Via async/await
const result = await validateRequiredEmail('test@example.com');

// Or via Promise
validateRequiredEmail('test@example.com').then((result) => {
  // Process result here
});

Finally, take action on the validation result:

if (result.state === 'valid') {
  submitResult({
    // It's recommended to use the value from the result
    // as transforms will be applied based on the type.
    email: result.value,
  });
} else {
  showError({
    // The message is the first matching one based on the
    // triggered validation error.
    email: result.message,
  });
}